Project Hephaistos recently identified seven M-dwarfs as possible Dyson Spheres (DS) candidates. We have cross-matched three of these candidates (A, B \& G) with radio sources detected in various all-sky surveys. The radio sources are offset from the Gaia stellar positions by ∼4.9, ∼0.4 and ∼5.0 arcseconds for candidates A, B, and G respectively. We propose that DOGs (Dust obscured galaxies) lying close to the line-of-sight of these M-dwarf stars significantly contribute to the measured WISE mid-IR flux densities in the WISE W3 and W4 wavebands. These three stars have therefore been misidentified as DS candidates. We also note that with an areal sky density of 9×10−6 per square arcsecond, Hot DOGs can probably account for the contamination of all 7 DS candidates drawn from an original sample of 5 million stars.
@article{arxiv.2405.14921,
title = {Background Contamination of the Project Hephaistos Dyson Spheres Candidates},
author = {Tongtian Ren and Michael A. Garrett and Andrew P. V. Siemion},
journal= {arXiv preprint arXiv:2405.14921},
year = {2024}
}